Field of the Invention
The present invention relates to a fuel cell system including a fuel cell stack formed by stacking a plurality of power generation cells and a stack case containing the fuel cell stack.
Description of the Related Art
For example, a solid polymer electrolyte fuel cell includes a membrane electrode assembly (MEA) having an electrolyte membrane. The electrolyte membrane is a solid polymer electrolyte membrane. An anode is provided on one surface of the electrolyte membrane, and a cathode is provided on the other surface of the electrolyte membrane. The membrane electrode assembly is sandwiched between separators (bipolar plates) to form a power generation cell. Normally, a predetermined number of the power generation cells are stacked together to form a fuel cell stack. For example, the fuel cell stack is mounted in a fuel cell vehicle (fuel cell electric automobile, etc.) as an in-vehicle fuel cell stack.
To the in-vehicle fuel cell stack, sways, vibrations, and other external loads tend to be applied. Therefore, in order to achieve the desired rigidity of the entire fuel cell stack, it has been common to adopt structure where the fuel cell stack is placed in a box. Further, Japanese Laid-Open Patent Publication No. 2014-096285 discloses an in-vehicle fuel cell system aiming to make it possible to easily achieve the lightweight, reliably receive the external load, and suitably protect the fuel cell stack.
The in-vehicle fuel cell system includes a fuel cell stack, and a box containing the fuel cell stack. The box includes two side plates, an upper plate, a lower plate, and a pair of end plates. At least the upper plate or the lower plate has a rectangular shape, and a pair of corners at a pair of diagonal positions are joined to the pair of end plates, and a pair of corners at the other diagonal positions are joined to the pair of side plates.